The present invention relates to carpet resistant to dust mite infestation and a method for making such carpet. In particular, the invention relates to a carpet having an acaracidal compound durably fixed to the base of the carpet tufts, thereby providing durable protection against dust mite infestation in a tufted carpet product.
Carpets are widely used for both residential and commercial applications. As used herein, the term xe2x80x9ccarpetxe2x80x9d includes broadloom products, rugs, as well as carpet tiles and cut carpets.
Finished carpets typically have a number of layers, e.g., a primary backing layer, an adhesive layer, and a secondary backing layer. Carpet is generally produced as tufted carpet where yarn, typically consisting of nylon, polyester, wool or polypropylene, is stitched into a primary backing that is prepared from a polymeric material. An adhesive material is then normally applied to the primary backing and, optionally, a secondary backing is affixed thereto.
It has become well recognized that carpeted floors, in particular, in residences, can harbor allergens. While a myriad of substances may cause allergic reactions in humans, acaracids, e.g., dust mites, are a common cause of allergies in adults and humans. Dust mites feed on dead skin cells from humans and animals that fall off the body and accumulate in the carpet. Such accumulation is generally seen at the carpet base.
A number of treatments have been proposed for ridding carpets of dust mite infestation. Such treatments generally have focused on topical treatment of carpet with acaracidal compounds, such as by shampooing or spraying. However, such treatments are usually only useful as short term solutions to the problem because they lack durability.
A longer term solution to reducing dust mite infestation in carpets has been proposed in U.S. Pat. No. 5,527,582, which disclosure is included herewith in its entirety by this reference. In this patent, an acaracidal compound is included in the adhesive backing that affixes the carpet yarn to the primary backing. The ""582 patent discloses that the acaracidal compound is released from the carpet backing by use of a carrier material, such as a plasticizer and/or surfactant. It is stated that the carrier material serves to allow the acaracidal material to migrate from the adhesive backing to the carpet fibers to kill or inactivate acarids present in the carpet. Such carrier material is necessary to achieve the acaracidal action in the carpets therein.
Although the method of the ""582 patent provides acaracidal activity that is more durable than that seen in topical treatments, because the acaracidal material migrates from the adhesive backing to the carpet fibers in a continuous and unregulated manner in the method disclosed therein, there will come a time when there remains little or no acaracidal compound in the carpet. Since carpets are generally intended to be useful for several years, the acaracidal activity of a carpet made according to the ""582 patent will not last as long as the carpet itself. As a result, the carpet will not be acarid-resistant for the life of the carpet.
In light of the above, it would be desirable to provide an acarid-resistant carpet, wherein the acarid-resistance lasts as long as the useful life of the carpet.
The invention relates to an acarcid-resistant carpet wherein an acaracidal compound is fixed at or near the base of the carpet tufts over which an adhesive layer is applied to the carpet tufts into a primary backing material. The invention further relates to methods of making such carpet.
Additional advantages of the invention will be set forth in part in the description that follows, and in part will be apparent from the description, or may be learned by practice of the invention. The advantages of the invention will be realized and attained by means of the elements and combination particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.